Simon Stevin

Simon Stevin was born in Bruges (Belgium) in 1548. He was an illegitimate child so he was raised by his mother, Cathelijne van der Poort. His father’s name was Antheunis Stevin. There isn’t much known about the youth of Simon. All we know is that he studied Latin and Greek and that he had a strong aptitude for maths and science. He translated his name into Latin: Simon Stevinius Brugensis.First he was a bookkeeper in Antwerp where he practised the double-entry bookkeeping fashioned after the method introduced by Pacioli in Italy almost a century earlier. Later he was a clerk in the tax office in Bruges.

He travelled to Germany, Scandinavia, Poland, Norway. Finally in 1580 he arrived in Leiden. While quartermaster in the Dutch army, Stevin invented a way of flooding the lowlands in the path of an invading army by opening selected sluices in dikes. He was an outstanding engineer who built windmills, locks and ports. He advised the Prince Maurice of Nassau on building fortifications for the war against Spain. To remind their victory against Spain, the prince founded a university at Leiden. In 1583 Simon Stevin went to that university where he studied science and maths. At the same time Prince Maurice of Nassau was studying there. He noticed that Stevin was a very intelligent man.

In 1592 Prince Maurice asked Stevin to come to The Hague for being his teacher. This was the beginning of a strong friendship. Stevin became not only the Prince’s mathematical and scientific tutor but also his military adviser who received a very important position in the Dutch army.

Stevin wrote a text-book, called "Wisconstige gedachtenissen"(mathematical memories), on all the mathematical and scientific subjects in which the prince was interested. Although Stevin was a great admirer of the theoretical treatises of Archimedes, there runs through the 11 books of this Flemish engineer a strain practicality that is more characteristic of the Renaissance period than the classical antiquity. In each of his books his iventiveness was evident, for each of his texts contained some innovation or improvement introduced by him.

Convinced that the Dutch language was excellently suited to scientific purposes, and that moreover the use of the Dutch language in science would contribute to the greatness of the nation, he wrote many of his works in Dutch, enriching the language with words of his own invention. In 1600, at the request of Prince Maurice, he directed the organization of a school of engineering at the University of Leyden, where Dutch, rather than Latin, was the language of instruction.

In 1608, when he was 60, he married and got 4 children. He died in 1620 at the age of 72, probably because of the riots between the Catholics and the Protestants. Himself he was a tolerant Catholic who was converted to a Protestant.

In Bruges, you can visit the Scientific Institute Simon Stevin and on the Simon Stevin square you'll find his statue.

1582: "Tafelen van interest midtsgaders de constructie der selver"; the oldest published book about calculations of interest.

1585: "De Thiende, leerende door ongehoorde lichticheyt allen rekeningen afveerdighen door heele ghetalen zonder ghebrokenen."Þ Contributions for general use of the system of decimal fractions. This work, by far of greatest importance, contained a complete decimal system consistently applied to integers and fractions. Stevin was in no sense the inventor of decimal fractions but he did introduce their use in maths demonstrating the simplicity, feasibility and advantage of the system in full, addressing himself to astronomers, surveyors, bankers and merchants. He did not write his decimal expressions with denominators ; instead, in a circle above or after each digit he wrote the power of ten assumed as a divisor. So instead of the words "tenth", "hundredth" and so on he used "prime", "second" etc.

Thus the value of pi, approximately, appeared as 3€ 1 4‚ 1ƒ 6„

In 1617 in the "Rhabdologia", the Scottish mathematician Napier referred to Stevin's arithmetic and proposed a point or a comma as the decimal separatrix. At the close of "De Thiende" Stevin added a plea for the application of the decimal system to all weights and measures and to coinage. "De Thiende", written originally in Dutch was also published in the same year in French "La Disme". An English translation by Robert Norton was printed in 1608.
1586 : "De beghinselen der weeghconst",
theory about the balance of figures on a sloped field.

1590 : "Het burgherlick leven", how to behave in society
He was the first who developed the theory about the parallelogram of forces

He discovered the hydrostatic paradox, precursor of Pascal's law.

Together with Johan Hugo de Groot, he did tests about the free fall. With those tests they proved the inaccuracy of Aristoteles who thought wrongly that the heaviest bodies fall fastest.

His book "Wisconstighe ghedachtenissen" deals with:

geometrical problems
trigonometry
science of perspective
bookkeeping
art of navigation
astronomy
Stevin used in his book "Stelreghel", meaning Algebra, the notation +,- and Ö . Where necessary he introduced new Dutch words like "wiskunde": mathematics in Dutch, meetkunde (geometry) , stelkunde (algebra), evenredig (proportional), evenwicht(balance), evenwijdig(parallel), reden(reason), omtrek(perimeter),...

He also invented "a sailing car". With this sailing car he reached at the beach of Scheveningen , with 25 passengers and a favourable wind, a speed of 35 km/h.

Note : His name use as a name of one of Jan de Nul ship for respecting his talent and his meritorious service to Belgium.